AUDIBLE SOUND MEASURING DEVICE

摘要

PROBLEM TO BE SOLVED: To surely discriminate and recognize not only the domestic audible sound signals but the foreign ones. SOLUTION: An audible sound table 12 stores one or plural frequencies included in a relevant audible sound signal, a time pattern including the presence or absence of a signal and the duration of the signal and other plural audible sound signals which may possibly be received in place of the relevant signal in every pattern number that specifies every audible sound signal. Then a specific pattern including the audible sound signals which are equal to the audible sound signals received from the public telephone networks 2 and 7 is decided among those patterns which are stored in the table 12, and it's recognized whether the audible sound signal of the pattern that is designated to every telephone operation is equal to the audible sound signal that is decided at a reception deciding part 11. If these two audible signals are not equal to each other, it's decided whether the audible sound signal decided at the part 11 is equal to another audible sound signal that may possibly be received in place of the audible sound signal of the designated pattern which is stored in the table 12.